Messages in this thread | | | Subject | Re: [PATCH v8 15/19] locking/rwsem: Adaptive disabling of reader optimistic spinning | From | Waiman Long <> | Date | Tue, 4 Jun 2019 14:04:34 -0400 |
| |
On 6/4/19 1:38 PM, Peter Zijlstra wrote: > On Tue, Jun 04, 2019 at 01:30:00PM -0400, Waiman Long wrote: >>> That's somewhat inconsistent wrt the type. I'll make it unsigned long, >>> as that is what makes most sense, given there's a pointer inside. >> Thank for spotting that, I will fix it. > I fixed a whole bunch of them; please find the modified patches here: > > https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/log/?h=locking/core
Thanks for reviewing the patches.
So how do you think about the overall state of this patchset? Do you think it is mature enough to go into 5.3?
Or if you want more time to think about solving the RT thread issue, we can merge just patches 1-16 and play with the last threes for some more time. I am fine with that too as improving RT tasks is not my main focus. I like patch 16 as it led me to discover the rwsem reader wakeup bug as I hit the negative dentry count WARN_ON message in my testing.
I worked on this owner merging patch mainly to alleviate the need to use cmpxchg for reader lock. cmpxchg_double() is certainly one possible solution though it won't work on older CPUs. We can have a config option to use cmpxchg_double as it may increase the size of other structures that embedded rwsem and impose additional alignment constraint.
Cheers, Longman
| |